CONSTRUCTION OF VARICELLA-ZOSTER VIRUS GENE LIBRARY 1) Varicella-zoster (VZV) causes chickenpox and shingles with complications of post-herpetic neuralgia, disseminated zoster, and localized visual, neurologic and arteriopathic disorders of considerable magnitude, all more frequent in the elderly. The purpose of this proposal is to clone the individual VZV genes in an in vitro transcription vector system. Based on DNA sequence analysis, the individual viral genes will be identified on the VZV DNA fragmants cloned in different plasmid vectors (pBR322, cosmid pHC79, Gemini plasmid vectors). Each gene will be cleaved from cloned DNA fragments by restriction endonucleases and blunt-ended with the Klenow fragment of DNA polymerase I. Appropriate synthetic linkers will be added and the DNA fragments will be subcloned into Gemini transcription vectors. If no appropriate restriction sites are available, DNA fragments will be digested with Bal-31 to produce shortened DNA fragments, blunt-ended, ligated to linkers and cloned into the plasmid vectors. PREPARATION OF VARICELLA-ZOSTER VIRUS SUBUNIT VACCINE 2) Varicella-zoster virus becomes latent in dorsal root ganglia and often reactivates years later to produce shingles (zoster), especially in immunosuppressed individuals and aging adults. At present, the only available vaccine against VZV infection is a live attenuated virus vacine which has been used mainly to immunize high-risk immunocompromised children. However, this vaccine is not ideal for vaccination of healthy infants as the virus is likely to establish latency and could potentially disseminate. Development of a subunit vaccine which induces lasting immunity but without potential for latency or dissemination provides an alternative for the control of VZV infection. The aim of this research proposal is to construct a subunit vaccine by insertion of VZV glycoprotein genes in the vaccinia virus gemone and to evaluate its immunization potential against VZV.